The overall purpose of the Administrative Core (Core A) is to provide scientific and administrative leadership, organizational structure, and effective and efficient means of communication and connectivity for all aspects of this multi-project program. An additional important function of the Administrative Core is to oversee and adjust as necessary its resources in support of the scientific projects, as well as the activities of Core B, which provides rhesus macaques and appropriate infrastructure support required for the animal model studies in all three scientific projects. In addition, the Administrative Core is responsible for organizing review of the program project by an External Advisory Committee. A strong administrative structure is essential for maintaining communication and promoting a strong sense of "joint purpose" among project leaders, core directors, and program staff. The Administrative Core will be directed by Dr. Eric Verdin (the principal investigator of the proposed program project and the project leader of Project 1) and Dr. Warner Greene (the project leader of Project 2). Advising Drs. Verdin and Greene will be an Executive Committee comprised of the principal investigators of the scientific projects and the directors of the cores, whose role is to facilitate communication and collaboration among program project investigators and staff, while providing appropriate administrative oversight and intervention necessary to accomplish the overall scientific goals of the program project. External review will be provided by an External Advisory Committee comprised of a distinguished panel of leaders in HIV research, whose role is to review the progress of the program project, to recommend where improvement or redirection is needed, and to brainstorm with project investigators about new ideas for future directions. The Administrative Core will provide a number of mechanisms, including teleconferencing capabilities at each site, a central electronic bulletin board, and manuscript sharing, that are designed to ensure that project investigators, core leaders, and project staff have ample opportunities for communication and interaction that promote scientific exchange and provide easy access to data and shared resources. The Administrative Core will provide fiscal and regulatory oversight for all program activities;organize monthly teleconferences of the Executive Committee, quarterly face-to-face meetings of all project investigators and staff, and an annual retreat with the External Advisory Committee and all project investigators and staff;and assist project investigators with dissemination of research findings.